21917689274 has 8 divisors (see below), whose sum is σ = 35405498100. Its totient is φ = 10115856576.

The previous prime is 21917689273. The next prime is 21917689289. The reversal of 21917689274 is 47298671912.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 20662050049 + 1255639225 = 143743^2 + 35435^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a super-2 number, since 2×21917689274² (a number of 21 digits) contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (21917689273) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 421493999 + ... + 421494050.

Almost surely, 2^21917689274 is an apocalyptic number.

21917689274 is a deficient number, since it is larger than the sum of its proper divisors (13487808826).

21917689274 is a wasteful number, since it uses less digits than its factorization.

21917689274 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 842988064.

The product of its digits is 3048192, while the sum is 56.

The spelling of 21917689274 in words is "twenty-one billion, nine hundred seventeen million, six hundred eighty-nine thousand, two hundred seventy-four".